Facebook today announced a tool to add friends to your Acquaintances list en masse. When you add friends to your Acquaintances list, they won't be notified they've been moved nor will they be unfriended. The only difference is you'll see fewer of their posts in your News Feed.

Back in September 2011, Facebook began rolling out improvements to its Friend Lists feature so that you can share content with just specific friends and/or to filter the News Feed with content from just specific friends. Here were the three improvements:

Smart lists – smart lists create themselves and stay up-to-date based on profile info your friends have in common with you (like your work, school, family, and city)

Close Friends and Acquaintances lists – see your best friends' photos and posts in one place, and see less from people you're not as close to

Better suggestions – add the right friends to your lists without a lot of effort

It was a good start, but Facebook soon realized that few users were actually using the lists. That's what today's update is for.

Here's how I described acquaintances at the time:

The Acquaintances list is for old classmates or business contacts that you want to see less of in your News Feed. Facebook will still use its algorithms to show you important things they post (like when they get married or move to a new city) but generally speaking you will see less of their updates.

If you have Facebook friends numbering in the three digit or even four digit range, chances are a lot them are acquaintances, and this new feature is for you.